1. Field of the Invention
The present invention relates to a router, and particularly relates to a router which identifies and controls P2P (Peer to Peer) traffic transmitted in networks and a P2P traffic information sharing system using the router.
2. Description of the Related Art
As the broad-band Internet has become popular, various P2P applications to exchange files through the Internet among the end users have appeared. A P2P application is file exchange software which enables the exchange of files, among client PCs, directly through the Internet.
For example, there is a P2P application specialized in specific files or a P2P application to enable exchange of any file without setting a server for file searching or file exchanging on the Internet (see Reference 1). The P2P application enables electronic commerce through the Internet with a third party in an individual level and also enables direct exchange of a large file, e.g., a music data file, etc., among individuals who can access the Internet.
Reference 1: Japanese Unexamined Patent Publication No. 2003-67276
However, at present, P2P traffic using the P2P application occupies a large part of the network bandwidth provided by a service provider (ISP) and consequently, use of other web services is restricted. This is because P2P traffic is generally used for a data transmission of a large file such as a music data.
FIG. 1 shows a comparative example of the P2P traffic and the traffic of other web services or the like.
As shown in FIG. 1, the P2P traffic occupies 70% to 80% of the network bandwidth provided by the service provider, and common Internet applications such as web browsing, and e-mail use only the remaining 20% to 30%.
Accordingly, P2P causes a congestion in the network and this brings about a degradation of the service quality of the entire network provided by the Internet provider. Moreover, this causes a problem that an equitable service cannot be provided to those who use P2P applications and those who do not use P2P applications.
In order to eliminate the above problems, the service provider arranges network devices to control the P2P traffic appropriately depending on the traffic volume. The network device must analyze the packet data of upper layers to determine the P2P traffic, therefore, network devices for P2P which can determine P2P traffic have been used.
Because the network device used for P2P requires more processes to discriminate the P2P traffic than the prior router, its data transmission ability is too small to use as a core in a large scale network. Therefore, the network devices have been used only at specific points in the network, corresponding to data transmission processibility. In order to effectively control P2P traffic in the entire network, it is necessary to provide network devices for P2P, corresponding to the respective traffic capacities, at all the required points in the network.
FIG. 2 shows an example of a known P2P traffic control.
In FIG. 2, edge routers 31 and 34, having a function as a network device intended to use for P2P in addition to a function as a router, are placed at reception points in subscriber's terminals 21 to 24.
In practice, the network devices specialized in the P2P are arranged together with the edge routers 31 and 34 having only a router function at the reception points, together with the network devices specialized in the P2P control the P2P traffic. On the other hand, routers 32, 33 and 35 in a network 11 with a large amount of traffic only have a function as a router.
In the present embodiment, only the edge routers 31 and 34 determine the kind of the data stream from subscriber's terminals 21 to 24 and discriminate the traffic using P2P application (P2P traffic) from the other traffic (Non-P2P traffic). The discriminated p2P traffic is, for example, limited in its transmission bandwidth or is discarded if necessary.
Consequently, the amount of the P2P traffic flowing from the edge routers 31 and 34 into the network 11 is limited whereby congestion in the network 11 due to the P2P traffic is prevented.
However, even if each P2P traffic flow into the network 11 is restricted in the edge routers 31 and 34, they are eventually joined in the network 11 when they are sent to an outside network 12. In this embodiment, the P2P traffic is joined in a router 33 in the network 11 and the joined traffic is sent to the network 12 via an edge router 35 provided at a peering point.
In this case, the traffic, which is increased due to joining, causes congestion between the router 33 and the edge router 35, and as a result, the P2P traffic control using the edge routers 31 and 34 does not work effectively. To avoid this, not only the edge routers 31 and 34 but all the routers 31 to 35 in the network 11 are required to have a function of a P2P-specialized network device or to be provided with the same. However, in this case, the data transmission processability is reduced due to the P2P traffic control in the routers 32, 33 and 35 in which the amount of the traffic in the network 11 is large.